Ultrasonic surgical instruments

ABSTRACT

A surgical instrument including a transducer and an end effector is disclosed. The transducer may be configured to generate an acoustic standing wave of vibratory motion along a longitudinal axis and may include a piezoelectric stack positioned along the longitudinal axis. A length of the transducer may be less than ½ of the wavelength of the acoustic standing wave. The end effector may be acoustically coupled to and may extend distally from the transducer along the longitudinal axis. A sum of the length of the transducer and a length of the end effector may be an integer multiple of ½ of the wavelength of the acoustic standing wave.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application claiming priority under35 U.S.C. §120 to U.S. patent application Ser. No. 13/852,539, filedMar. 28, 2013, entitled “ULTRASONIC SURGICAL INSTRUMENTS,” now U.S.Patent Application Publication No. 2013/0226208, which is a divisionalapplication claiming priority under 35 U.S.C. §121 to U.S. patentapplication Ser. No. 11/888,171, filed Jul. 31, 2007, entitled“ULTRASONIC SURGICAL INSTRUMENTS,” now U.S. Pat. No. 8,430,898, theentire disclosures of which are hereby incorporated by reference herein.

BACKGROUND

Ultrasonic instruments, including both hollow core and solid coreinstruments are used for the safe and effective treatment of manymedical conditions. Ultrasonic instruments, and particularly solid coreultrasonic instruments, are advantageous because they may be used to cutand/or coagulate tissue using energy in the form of mechanicalvibrations transmitted to a surgical end effector at ultrasonicfrequencies. Ultrasonic vibrations, when transmitted to organic tissueat suitable energy levels and using a suitable end effector, may be usedto cut, dissect or coagulate tissue or to separate muscle tissue offbone. Ultrasonic instruments may be used for open procedures orminimally invasive procedures, such as endoscopic or laparoscopicprocedures, wherein the end effector is passed through a trocar to reachthe surgical site.

Activating or exciting the single or multiple element end effector(e.g., cutting blade, ball coagulator) of such instruments at ultrasonicfrequencies induces longitudinal, transverse or tortional vibratorymovement that generates localized heat within adjacent tissue,facilitating both cutting and coagulating. Because of the nature ofultrasonic instruments, a particular ultrasonically actuated endeffector may be designed to perform numerous functions, including, forexample, cutting and coagulating.

Ultrasonic vibration is induced in the surgical end effector byelectrically exciting a transducer, for example. The transducer may beconstructed of one or more piezoelectric or magnetostrictive elements inthe instrument hand piece. Vibrations generated by the transducersection are transmitted to the surgical end effector via an ultrasonicwaveguide extending from the transducer section to the surgical endeffector. The waveguides and end effectors may be designed to resonateat the same frequency as the transducer. Therefore, when an end effectoris attached to a transducer the overall system frequency is the samefrequency as the transducer itself.

The transducer and the end effector may be designed to resonate at twodifferent frequencies and when joined or coupled may resonate at a thirdfrequency. The zero-to-peak amplitude of the longitudinal ultrasonicvibration at the tip, d, of the end effector behaves as a simplesinusoid at the resonant frequency as given by:

d=A sin(ωt)

where:

-   ω=the radian frequency which equals a times the cyclic frequency, f,    and-   A=the zero-to-peak amplitude.    The longitudinal excursion is defined as the peak-to-peak (p-t-p)    amplitude, which is just twice the amplitude of the sine wave or 2A.

Ultrasonic surgical instruments may be divided into two types, singleelement end effector devices and multiple-element end effector devices.Single element end effector devices include instruments such as scalpels(e.g., blades, sharp hook blades, dissecting hook blades, curved blades)and ball coagulators. Single-element end effector instruments havelimited ability to apply blade-to-tissue pressure when the tissue issoft and loosely supported. Substantial pressure may be necessary toeffectively couple ultrasonic energy to the tissue. This inability tograsp the tissue results in a further inability to fully coapt tissuesurfaces while applying ultrasonic energy, leading to less-than-desiredhemostasis and tissue joining. In these cases, multiple-element endeffectors may be used. Multiple-element end effector devices, such asclamping coagulators, include a mechanism to press tissue against anultrasonic blade that can overcome these deficiencies.

One drawback of existing ultrasonic instruments is their size. The largesize and bulkiness of existing ultrasonic instruments can make it moredifficult for clinicians to manipulate the instruments in surgicalenvironments where fine movement is required and can also obstruct thevision of the clinician. This may limit the usefulness of ultrasonicinstruments in small surgical sites. Also, because of the bulkiness ofexisting transducers, many existing ultrasonic instruments position thetransducer proximal from the end effector, requiring an extended, andoften relatively inflexible wave guide. As a result, articulation of theend effector and blade may be difficult or impossible. This limits theusefulness of existing ultrasonic instruments in endoscopic andlaparoscopic surgical environments.

SUMMARY

In one general aspect, the various embodiments are directed to asurgical instrument. The surgical instrument may comprise a transducerand an end effector. The transducer may be configured to generate anacoustic standing wave of vibratory motion along a longitudinal axis andmay comprise a piezoelectric stack positioned along the longitudinalaxis. A length of the transducer may be less than ½ of the wavelength ofthe acoustic standing wave. The end effector may be acoustically coupledto and may extend distally from the transducer along the longitudinalaxis. A sum of the length of the transducer and a length of the endeffector may be an integer multiple of ½ of the wavelength of theacoustic standing wave.

In another general aspect, the various embodiments are directed toanother surgical instrument comprising a transducer and an end effector.The transducer may be configured to provide a wave of longitudinalvibratory motion along a longitudinal axis and may comprise apiezoelectric stack positioned along the longitudinal axis. A length ofthe transducer may be greater than or equal to ¼ of the wavelength andless than ½ of the wavelength of the wave. The end effector may becoupled to and may extend distally from the transducer along thelongitudinal axis. A sum of the length of the transducer and a length ofthe end effector may be an integer multiple of ½ of the wavelength ofthe wave.

In yet another general aspect, the various embodiments are directed toanother surgical instrument comprising a transducer and an end effector.The transducer may be configured to generate an acoustic wave ofvibratory motion along a longitudinal axis at a predetermined frequency.A length of the transducer may be less than ½ of the wavelength of theacoustic wave. The end effector may be coupled to a distal end of thetransducer. The end effector may comprise a waveguide that may becoupled to and may extend distally from the transducer, and a blade thatmay be coupled to and may extend distally from the waveguide. A sum ofthe length of the transducer, a length of the waveguide, and a length ofthe blade may be an integer multiple of ½ of the wavelength of theacoustic wave.

FIGURES

The novel features of the various embodiments are set forth withparticularity in the appended claims. The various embodiments, however,both as to organization and methods of operation, together with furtherobjects and advantages thereof, may best be understood by reference tothe following description, taken in conjunction with the accompanyingdrawings as follows.

FIG. 1 illustrates one embodiment of an ultrasonic system.

FIG. 2 illustrates one embodiment of a connection union/joint for anultrasonic instrument.

FIG. 3 illustrates an exploded perspective view of one embodiment of asurgical instrument that may be employed with the ultrasonic systemshown in FIG. 1.

FIG. 4 illustrates one embodiment of a chart showing the displacement ofa standing waveform over a full wavelength.

FIG. 5 illustrates one embodiment of a full-wavelength ultrasonictransducer having two mounting points comprising flanges.

FIG. 6 illustrates one embodiment of a full-wavelength ultrasonictransducer having two mounting points defining grooves.

FIGS. 7-8 illustrate embodiments of a full-wavelength ultrasonictransducer having one mounting point comprising a flange and onemounting point defining a groove.

FIG. 9 illustrates one embodiment of a full-wavelength ultrasonictransducer having two mounting points, each comprising a pair offlanges.

FIG. 10 illustrates one embodiment of a portion of an ultrasonic deviceincluding a housing, a transducer and an end effector.

FIG. 11 illustrates one embodiment of a portion of an ultrasonic deviceincluding an ultrasonic transducer and end effector.

FIG. 12 illustrates one embodiment of a quarter-wavelength ultrasonictransducer.

FIG. 12A illustrates a cut-away view of one embodiment of thequarter-wave ultrasonic transducer shown in FIG. 12.

FIG. 13 illustrates one embodiment of an ultrasonic transducer.

FIG. 14 illustrates one embodiment of an ultrasonic transducer havingfirst and second piezoelectric stacks.

FIG. 15 illustrates one embodiment of an ultrasonic instrument.

FIG. 16 illustrates one embodiment of an ultrasonic instrument havingfinger loops.

FIG. 17 illustrates one embodiment of the ultrasonic instrument shown inFIG. 16.

FIG. 18 illustrates one embodiment of an ultrasonic instrument.

FIG. 19 illustrates one embodiment of the ultrasonic instrument shown inFIG. 18.

FIG. 20 illustrates one embodiment of an ultrasonic end effector andtransducer assembly positioned at the distal end of a flexible member.

FIG. 21 illustrates one embodiment of an surgical instrument for use inan endoscopic or laparoscopic environment.

FIG. 22 illustrates one embodiment of the surgical instrument shown inFIG. 21.

FIG. 23 illustrates one embodiment of the surgical instrument shown inFIG. 21.

FIG. 24 illustrates one embodiment of the surgical instrument shown inFIG. 21 including a flexible lasso.

FIG. 25 illustrates one embodiment of the surgical instrument shown inFIG. 24.

FIG. 26 illustrates one embodiment of the surgical instrument shown inFIG. 24.

DESCRIPTION

Before explaining the various embodiments in detail, it should be notedthat the embodiments are not limited in their application or use to thedetails of construction and arrangement of parts illustrated in theaccompanying drawings and description. The illustrative embodiments maybe implemented or incorporated in other embodiments, variations andmodifications, and may be practiced or carried out in various ways. Forexample, the surgical instruments and blade configurations disclosedbelow are illustrative only and not meant to limit the scope orapplication thereof. Furthermore, unless otherwise indicated, the termsand expressions employed herein have been chosen for the purpose ofdescribing the illustrative embodiments for the convenience of thereader and are not to limit the scope thereof.

Examples of ultrasonic surgical instruments and blades are disclosed inU.S. Pat. Nos. 5,322,055 and 5,954,736, 6,309,400 B2, 6,278,218B1,6,283,981 B1, and 6,325,811 B1, which are incorporated herein byreference in their entirety. These references disclose ultrasonicsurgical instrument designs and blade designs where a longitudinal modeof the blade is excited. The result is a longitudinal standing wavewithin the instrument. Accordingly, the instrument has nodes, where thelongitudinal motion is equal to zero, and anti-nodes, where thelongitudinal motion is at its maximum. The instrument's tissue effectoris often positioned at an anti-node, maximizing its longitudinal motion.

Various embodiments will now be described to provide an overallunderstanding of the principles of the structure, function, manufacture,and use of the devices and methods disclosed herein. One or moreexamples of these embodiments are illustrated in the accompanyingdrawings. Those of ordinary skill in the art will understand that thedevices and methods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the various embodiments is defined solely by the claims.The features illustrated or described in connection with one exemplaryembodiment may be combined with the features of other embodiments. Suchmodifications and variations are intended to be included within thescope of the claims.

FIG. 1 illustrates one embodiment of an ultrasonic system 10. Theultrasonic system 10 may comprise an ultrasonic signal generator 12coupled to an ultrasonic transducer 14, a hand piece assembly 60comprising a hand piece housing 16, and an ultrasonically actuatablesingle element end effector or ultrasonically actuatable blade 50. Theultrasonic transducer 14, which is known as a “Langevin stack”,generally includes a transduction portion 18, a first resonator portionor end-bell 20, and a second resonator portion or fore-bell 22, andancillary components. The total construction of these portions is aresonator. The ultrasonic transducer 14 is preferably an integral numberof one-half system wavelengths (nλ/2: wherein “n” is any positiveinteger; e.g., n=1, 2, 3 . . . ) in length as will be described in moredetail later. An acoustic assembly 24 includes the ultrasonic transducer14, a nose cone 26, a velocity transformer 28, and a surface 30.

It will be appreciated that the terms “proximal” and “distal” are usedherein with reference to a clinician gripping the hand piece assembly60. Thus, the end effector 50 is distal with respect to the moreproximal hand piece assembly 60. It will be further appreciated that,for convenience and clarity, spatial terms such as “top” and “bottom”also are used herein with respect to the clinician gripping the handpiece assembly 60. However, surgical instruments are used in manyorientations and positions, and these terms are not intended to belimiting and absolute.

The distal end of the end-bell 20 is connected to the proximal end ofthe transduction portion 18, and the proximal end of the fore-bell 22 isconnected to the distal end of the transduction portion 18. Thefore-bell 22 and the end-bell 20 have a length determined by a number ofvariables, including the thickness of the transduction portion 18, thedensity and modulus of elasticity of the material used to manufacturethe end-bell 20 and the fore-bell 22, and the resonant frequency of theultrasonic transducer 14. The fore-bell 22 may be tapered inwardly fromits proximal end to its distal end to amplify the ultrasonic vibrationamplitude as the velocity transformer 28, or alternately may have noamplification. A suitable vibrational frequency range may be about 20 Hzto 120 kHz and a well-suited vibrational frequency range may be about30-100 kHz and one example operational vibrational frequency may beapproximately 55.5 kHz, for example.

Piezoelectric stack 31 may include one or more piezoelectric elements32, which may be fabricated from any suitable material, such as, forexample, lead zirconate-titanate, lead meta-niobate, lead titanate,barium titanate or other piezoelectric ceramic material. Each ofpositive electrodes 34, negative electrodes 36, and the piezoelectricelements 32 may have a bore extending through the center. The positiveand negative electrodes 34 and 36 are electrically coupled to wires 38and 40, respectively. The wires 38 and 40 are encased within a cable 42and electrically connectable to the ultrasonic signal generator 12 ofthe ultrasonic system 10.

The ultrasonic transducer 14 of the acoustic assembly 24 converts theelectrical signal from the ultrasonic signal generator 12 intomechanical energy that results in primarily a standing acoustic wave oflongitudinal vibratory motion of the ultrasonic transducer 14 and theend effector 50 at ultrasonic frequencies. In another embodiment, thevibratory motion of the ultrasonic transducer may act in a differentdirection. For example, the vibratory motion may comprise a locallongitudinal component of a more complicated motion of the tip of theultrasonic system 10. A suitable generator is available as model numberGEN01, from Ethicon Endo-Surgery, Inc., Cincinnati, Ohio. When theacoustic assembly 24 is energized, a vibratory motion standing wave isgenerated through the acoustic assembly 24. The ultrasonic system 10 maybe designed to operate at a resonance such that an acoustic standingwave pattern of a predetermined amplitude is produced. The amplitude ofthe vibratory motion at any point along the acoustic assembly 24 maydepend upon the location along the acoustic assembly 24 at which thevibratory motion is measured. A minimum or zero crossing in thevibratory motion standing wave is generally referred to as a node (e.g.,where motion is usually minimal), and a local absolute value maximum orpeak in the standing wave is generally referred to as an anti-node(e.g., where motion is usually maximal). The distance between ananti-node and its nearest node is one-quarter wavelength (λ/4).

The wires 38 and 40 transmit an electrical signal from the ultrasonicsignal generator 12 to the positive electrodes 34 and the negativeelectrodes 36. The piezoelectric elements 32 are energized by theelectrical signal supplied from the ultrasonic signal generator 12 inresponse to a switch 44 to produce an acoustic standing wave in theacoustic assembly 24. The switch 44 may be configured to be actuated bya clinician's foot. The electrical signal causes the piezoelectricelements 32 to expand and contract in a continuous manner along the axisof the voltage gradient, producing longitudinal waves of ultrasonicenergy. The straining of the elements causes large alternatingcompressional and tensile forces within the material. These forces inthe piezoelectric elements 32 manifest as repeated small displacementsresulting in large alternating compression and tension forces within thematerial. The repeated small displacements cause the piezoelectricelements 32 to expand and contract in a continuous manner along the axisof the voltage gradient, producing longitudinal waves of ultrasonicenergy. The ultrasonic energy is transmitted through the acousticassembly 24 to the end effector 50 via a transmission component orultrasonic transmission waveguide 104. According to various embodiments,the waveguide 104, end effector 50 and blade 52 may all be referred togenerally as the end effector.

In order for the acoustic assembly 24 to deliver energy to the endeffector 50, all components of the acoustic assembly 24 must beacoustically coupled to the end effector 50. The distal end of theultrasonic transducer 14 may be acoustically coupled at the surface 30to the proximal end of the ultrasonic transmission waveguide 104 by athreaded connection such as a stud 48.

The components of the acoustic assembly 24 are preferably acousticallytuned such that the length of any assembly is an integral number ofone-half wavelengths (nλ/2), where the wavelength λ is the wavelength ofa pre-selected or operating longitudinal vibration drive frequency f_(d)of the acoustic assembly 24, and where n is any positive integer. It isalso contemplated that the acoustic assembly 24 may incorporate anysuitable arrangement of acoustic elements.

The ultrasonic end effector 50 may have a length substantially equal toan integral multiple of one-half system wavelengths (λ/2). A distal endor blade 52 of the ultrasonic end effector 50 may be disposed near anantinode in order to provide the maximum longitudinal excursion of thedistal end. When the transducer assembly is energized, the distal end 52of the ultrasonic end effector 50 may be configured to move in the rangeof, for example, approximately 10 to 500 microns peak-to-peak, andpreferably in the range of about 30 to 150 microns at a predeterminedvibrational frequency.

The ultrasonic end effector 50 may be coupled to the ultrasonictransmission waveguide 104. The ultrasonic end effector 50 and theultrasonic transmission guide 104 as illustrated are formed as a singleunit construction from a material suitable for transmission ofultrasonic energy such as, for example, Ti6Al4V (an alloy of Titaniumincluding Aluminum and Vanadium), Aluminum, Stainless Steel, or othersuitable materials. Alternately, the ultrasonic end effector 50 may beseparable (and of differing composition) from the ultrasonictransmission waveguide 104, and coupled by, for example, a stud, weld,glue, quick connect, or other suitable known methods. The ultrasonictransmission waveguide 104 may have a length substantially equal to anintegral number of one-half system wavelengths (λ/2), for example. Theultrasonic transmission waveguide 104 may be preferably fabricated froma solid core shaft constructed out of material suitable to propagateultrasonic energy efficiently, such as the titanium alloy discussedabove, (e.g., Ti-6Al-4V) or any suitable aluminum alloy, or otheralloys, for example.

The ultrasonic transmission waveguide 104 comprises a longitudinallyprojecting attachment post 54 at a proximal end to couple to the surface30 of the ultrasonic transmission waveguide 104 by a threaded connectionsuch as the stud 48. In the embodiment illustrated in FIG. 1, theultrasonic transmission waveguide 104 comprises a plurality ofstabilizing silicone rings or compliant supports 56 positioned at aplurality of nodes. The silicone rings 56 dampen undesirable vibrationand isolate the ultrasonic energy from an outer sheath 58 assuring theflow of ultrasonic energy in a longitudinal direction to the distal end52 of the end effector 50 with maximum efficiency.

As shown in FIG. 1, the outer sheath 58 protects a user of theultrasonic instrument 10 and a patient from the ultrasonic vibrations ofthe ultrasonic transmission waveguide 104. The sheath 58 generallyincludes a hub 62 and an elongated tubular member 64. The tubular member64 is attached to the hub 62 and has an opening extending longitudinallytherethrough. The sheath 58 may be threaded or snapped onto the distalend of the housing 16. The ultrasonic transmission waveguide 104 extendsthrough the opening of the tubular member 64 and the silicone rings 56isolate the ultrasonic transmission waveguide 104 from the outer sheath58. The outer sheath 58 may be attached to the waveguide 104 with anisolator pin 112. The hole in the waveguide 104 may occur nominally at adisplacement. The waveguide 104 may screw or snap onto the hand pieceassembly 60 by the stud 48. The flat portions of the hub 62 may allowthe assembly to be torqued to a required level.

The hub 62 of the sheath 58 is preferably constructed from ULTEM®, andthe tubular member 64 is fabricated from stainless steel. Alternatively,the ultrasonic transmission waveguide 104 may have polymeric materialsurrounding it to isolate it from outside contact.

The distal end of the ultrasonic transmission waveguide 104 may becoupled to the proximal end of the end effector 50 by an internalthreaded connection, preferably at or near an antinode. It iscontemplated that the end effector 50 may be attached to the ultrasonictransmission waveguide 104 by any suitable means, such as a welded jointor the like. Although the end effector 50 may be detachable from theultrasonic transmission waveguide 104, it is also contemplated that theend effector 50 and the ultrasonic transmission waveguide 104 may beformed as a single unitary piece.

FIG. 2 illustrates one embodiment of a connection union/joint 70 for anultrasonic instrument. The connection union/joint 70 may be formedbetween the attachment post 54 of the ultrasonic transmission waveguide104 and the surface 30 of the velocity transformer 28 at the distal endof the acoustic assembly 24. The proximal end of the attachment post 54comprises a female threaded substantially cylindrical recess 66 toreceive a portion of the threaded stud 48 therein. The distal end of thevelocity transformer 28 also may comprise a female threadedsubstantially cylindrical recess 68 to receive a portion of the threadedstud 40. The recesses 66, 68 are substantially circumferentially andlongitudinally aligned. In another embodiment (not shown), the stud isan integral component of the end of the ultrasonic transducer. Forexample, the treaded stud and the velocity transformer may be of asingle unit construction with the stud projecting from a distal surfaceof the velocity transformer at the distal end of the acoustic assembly.In this embodiment, the stud is not a separate component and does notrequire a recess in the end of the transducer.

FIG. 3 illustrates an exploded perspective view of one embodiment of asterile ultrasonic surgical instrument 100. The ultrasonic surgicalinstrument 100 may be employed with the above-described ultrasonicsystem 10. However, as described herein, those of ordinary skill in theart will understand that the various embodiments of the ultrasonicsurgical instruments disclosed herein as well as any equivalentstructures thereof could conceivably be effectively used in connectionwith other known ultrasonic surgical instruments without departing fromthe scope thereof. Thus, the protection afforded to the variousultrasonic surgical blade embodiments disclosed herein should not belimited to use only in connection with the exemplary ultrasonic surgicalinstrument described above.

The ultrasonic surgical instrument 100 may be sterilized by methodsknown in the art such as, for example, gamma radiation sterilization,Ethelyne Oxide processes, autoclaving, soaking in sterilization liquid,or other known processes. In the illustrated embodiment, an ultrasonictransmission assembly 102, which may be generally referred to as the endeffector, may include the ultrasonic end effector 50 and the ultrasonictransmission waveguide 104. The ultrasonic end effector 50 and theultrasonic transmission waveguide 104 are illustrated as a single unitconstruction from a material suitable for transmission of ultrasonicenergy such as, for example, Ti6Al4V (an alloy of Titanium includingAluminum and Vanadium), Aluminum, Stainless Steel, or other knownmaterials. Alternately, the ultrasonic end effector 50 may be separable(and of differing composition) from the ultrasonic transmissionwaveguide 104, and coupled by, for example, a stud, weld, glue, quickconnect, or other known methods. The ultrasonic transmission waveguide104 may have a length substantially equal to an integral number ofone-half system wavelengths (nλ/2), for example. The ultrasonictransmission waveguide 104 may be preferably fabricated from a solidcore shaft constructed out of material that propagates ultrasonic energyefficiently, such as titanium alloy (e.g., Ti-6Al-4V) or an aluminumalloy, for example.

In the embodiment illustrated in FIG. 3, the ultrasonic transmissionwaveguide 104 is positioned in an outer sheath 106 by a mounting O-ring108 and a sealing ring 110. One or more additional dampers or supportmembers (not shown) also may be included along the ultrasonictransmission waveguide 104. The ultrasonic transmission waveguide 104 isaffixed to the outer sheath 106 by a mounting pin 112 that passesthrough mounting holes 114 in the outer sheath 106 and a mounting slot116 in the ultrasonic transmission waveguide 104.

FIG. 4 illustrates one cycle or wavelength of a standing waveform 400 asit would be formed in a full-wavelength transducer. The length of thewaveform 400, and thus the length of the transducer, may depend onsystem frequency and the material from which the transducer is made. Forexample, in a transducer made of titanium and excited at a frequency of55.5 kHz, one wavelength may be approximately 3.44 inches. Because it isa full-wavelength, the waveform 400 includes two nodes 402 where thedisplacement is zero. These are the zero-displacement nodes 402 and theyoccur at λ/4 and 3λ/4, or λ/4 from the respective edges of the waveform400 on the x-axis. Mounting points for the transducer may be positionedto correspond to the zero-displacement nodes 402.

FIGS. 5-9 illustrate embodiments of full-wavelength ultrasonictransducers that may be used in any suitable ultrasonic systemincluding, for example, the system 10 described above. Because thefull-wavelength transducers are longer than typical half-wavelengthtransducers, they may include a longer piezoelectric stack. For thisreason, full-wavelength transducers may be able to deliver powercomparable to that of existing larger-diameter half-wavelengthtransducers. Also, full-wavelength transducers, such as the embodimentsshown in FIGS. 5-9 may include multiple mounting points. This mayprovide increased resistance to prevent the transducers from pivotingwithin the hand piece housing in response to forces applied at the endeffector, and also may provide increased damping to prevent unwantedvibration modes such as transverse and tortional.

FIG. 5 illustrates one embodiment of a full-wavelength ultrasonictransducer 500 having two mounting points 506, 508 comprising flanges514, 516. The transducer 500 may generally include a piezoelectric stack510, which may include a series of piezoelectric elements 512.Optionally, the transducer 500 may be divided into an active stage 504,including the piezoelectric stack 510, and a gain stage 502, which mayprovide amplitude gain. The gain stage 502, for example, may involve achange in the cross-sectional area of the transducer 500 positioned ator near the zero displacement node 402. As described above, the mountingpoints 514, 516 may be located at the respective zero-displacement nodesin the transducer 500. This may prevent significant amounts oftransverse vibration from being transferred from the transducer 500 tothe hand piece housing (not shown).

The mounting points 506, 508 may take any suitable form. For example, inthe embodiment shown in FIG. 5, the mounting points 506, 508 compriseflanges 514, 516 raised above the surface the transducer 500. The handpiece housing, or other frame member, may then include correspondingshapes for receiving the flanges 514, 516. FIG. 6 illustrates oneembodiment of a full-wavelength ultrasonic transducer 600 having twomounting points 506, 508 defining grooves 530, 528. The hand piecehousing or other frame member (not shown) may include a correspondingfeature for coupling with the grooves 530, 528. Also, for example, anO-ring or other type of elastomeric member (not shown) may be positionedwithin one or both of the groove 530, 528. The O-ring may interface withthe hand piece housing or other frame member. FIG. 7 illustrates oneembodiment of a full-wavelength ultrasonic transducer 700 having onemounting point 506 defining a groove 526 and one mounting point 508comprising a flange 524. FIG. 8 illustrates one embodiment of afull-wavelength ultrasonic transducer 800 having one mounting point 506comprising a flange 522 and one mounting point 508 defining a groove520. FIG. 9 illustrates one embodiment of a full-wavelength ultrasonictransducer 900 having two mounting points 506, 508. Each of the mountingpoints 506 508 may comprise a pair of flanges which together definegrooves 532, 534. In this way, an O-ring may be held stationary by theflanges without the need for a groove extending into the transducer 500.

FIG. 10 illustrates an embodiment of a portion 1000 of an ultrasonicdevice including a housing 1002, a transducer 1004 and an end effector1006. The transducer 1004 may include mounting points 1008 and 1009 ofdifferent dimensions. For example, in the embodiment shown in FIG. 10,the distal mounting point 1008 is shown with a smaller dimension thanthe proximal mounting point 1009. This may simplify manufacturing byallowing the transducer to be inserted into the housing 1002 from theproximal end.

FIG. 11 illustrates one embodiment of a portion of an ultrasonic deviceincluding an ultrasonic transducer 1100 and end effector 1102. Thetransducer 1100 may include a piezoelectric stack 1104 comprising one ormore piezoelectric disks 1106. The transducer 1100 may be constructed asa unity gain or near unity gain transducer. For example, the amplitudeof the standing wave at the distal end of the transducer 1100 may besubstantially similar to the amplitude of the standing wave at theproximal end of the transducer 1100. In one example embodiment, theamplitude at the distal end of the transducer 1100 may be between 1 and5 microns peak-to-peak. As described above, it may be desirable for theend effector 1102 to displace at an amplitude of, for example, between10 and 100 microns peak-to-peak. Accordingly, it may be desirable toconfigure the end effector 1102 to implement an amplitude gain betweenits proximal and distal ends. The end effector 1102 is shown with aseries of relatively large diameter sections 1110 and relatively smalldiameter sections 1108. Each transition from a large diameter section1110 to a small diameter section 1108 may bring about an amplitude gainwhen the transition occurs near a zero-displacement node. According tovarious embodiments, the total amplitude gain of the transducer 1100 andend effector 1102 may be between about 10 and 50. For example, the totalamplitude gain may be about 40.

FIGS. 12-14 show embodiments of various transducers with a length lessthan one half (½) of one wavelength. Because of their small size, theembodiments shown in FIGS. 12-14 may be useful in smaller ultrasonicapplications where lower ultrasonic power is required. In general,components in ultrasonic surgical instruments are dimensioned asintegral multiples of half wavelengths (nλ/2). For example, transducers,waveguides and end effectors have a length that is usually an integralmultiple of λ/2. Individual components, however, may have a length ofless than λ/2, provided that the system as a whole (e.g., the transducerplus any end effector) has a length that is a multiple of λ/2. Forexample, a transducer, according to various embodiments, may have alength of between λ/4 and λ/2.

FIG. 12 illustrates one embodiment of a quarter-wavelength (λ/4)ultrasonic transducer 1200. The transducer 1200 may include a flange1208 and a mass 1210 with a piezoelectric stack 1204 positionedtherebetween. The flange 1208 and mass may be made from any suitablematerial including, for example, metallic materials such as titanium oran alloy thereof. According to various embodiments, the flange 1208 mayinclude an O-ring or other elastomeric material member (not shown) thatmay provide sealing as well as damping of vibrations within the flange1208. The O-ring may be mounted within a groove or other feature of theflange (not shown), for example, as illustrated above in FIGS. 5-9.Also, according to various embodiments, the flange 1208 may be replacedwith a second mass having radial dimensions similar to those of thepiezoelectric stack 1204 and the mass 1210. FIG. 12A illustrates acut-away view of one embodiment of the quarter-wave ultrasonictransducer 1200 illustrating a stud 1212. The stud 1212 may engage theelements 1206 of the piezoelectric stack 1204, placing them incompression. This may prevent the individual piezoelectric elements 1206from being subjected to tension, which may cause mechanical failure.

In the embodiment shown in FIG. 12, a zero-displacement node 1202 of thetransducer 1200 is indicated. The node 1202 may be located one quarterof one wavelength from the opposite edge 1220 of the transducer 1200.FIG. 13 illustrates one embodiment of an ultrasonic transducer 1300 thatmay be longer than a quarter wavelength. For example, the transducer1300 may be dimensioned so that the node 1202 falls within flange 1208.In this way, the transducer stack 1204 may be closer to the node 1202.This may increase the effectiveness of the stack 1204. FIG. 14illustrates one embodiment of an ultrasonic transducer 1400 having firstand second piezoelectric stacks 1408 and 1404. The stacks 1404 and 1408may be separated by a flange 1416, with masses 1412 and 1414 on therespective ends. According to various embodiments, the transducer 1400may be between λ/4 and λ/2 in length.

FIGS. 15-19 illustrate embodiments of ultrasonic surgical devices havingfirst and second operation members pivotable towards one another about apivot point. A first operation member may comprise a transducer and anend effector coupled to the transducer. A second operation member maycomprise a clamp pad. When the operation members are pivoted toward oneanother the clamp pad may be brought toward the end effector. Thesurgical instruments may be arranged according to any suitableconfiguration. For example, the embodiments shown in FIG. 15-17 may bearranged in a tweezer-like configuration. Also, for example, theembodiments shown in FIGS. 18-19 may be arranged with a scissor orpistol-like grip.

FIG. 15 illustrates one embodiment of a surgical instrument 1500 havinga first member 1504 and a second member 1502. The members 1502 may bepivotable toward one another about pivot point 1520. A support member1512 may be positioned at the pivot point 1520 and may resist movementsof the members 1504, 1502 toward or away from one another. According tovarious embodiments, the member 1502 may comprise a transducer assembly1505 and an end effector 1506. The end effector 1506 may include awaveguide assembly 1507 and a blade 1508. A port 1509 may receive one ormore wires (not shown) connecting the transducer assembly 1505 to asignal generator (not shown in FIG. 15). The end effector 1506 maycomprise a waveguide and a protective sheath to prevent the waveguidefrom contacting tissue. The blade 1508 may operate as described above tocut and/or coagulate tissue. When the members 1504 and 1502 are pivotedtogether, the end effector 1508 may come into contact with the clamp pad1510, allowing a clinician to apply pressure to tissue in contact withthe blade 1508.

FIG. 16 illustrates one embodiment of an ultrasonic instrument 1600similar to instrument 1500 and including finger loops 1604. The surgicalinstrument 1600 also may include a hinge 1602 at pivot point 1520. Thehinge 1602 may allow the members 1502, 1504 to pivot freely about thepivot point 1520. The finger loops 1604 may be positioned on the members1502, 1504 distally from the pivot point 1520. A clinician may use thefinger loops 1604 to manipulate the members 1502, 1504. Also, accordingto various embodiments, the finger loops 1604 may be rotatable relativeto the members 1502, 1504. For example, FIG. 17 illustrates oneembodiment of the instrument 1600 with the finger loops 1604 rotated 90°relative to their position as shown in the embodiment of FIG. 16. Itwill be appreciated that the finger loops 1604 may be provided withholes large enough to fit multiple fingers.

FIGS. 18-19 illustrate one embodiment of an ultrasonic instrument 1800.The instrument 1800 includes a first member 1802 and a second member1804 pivotable towards one another about pivot point 1806. The firstmember 1802 may comprise a transducer assembly 1812 and an end effector1808. The end effector 1808 includes a waveguide assembly 1810 and ablade 1811. The second member 1804 may comprise a clamp pad 1814opposite blade 1811. When the members 1802, 1804 are pivoted towards oneanother, the clamp pad 1814 may come into contact with the blade 1811.In this way, a clinician may exert pressure on tissue in contact withthe end effector 1808. Finger loops 1816 and 1818 may be positionedrelative to the pivot point 1806 to allow a clinician to pivot themembers 1802 and 1804 about the pivot point 1806 in a scissor-likemanner. The finger loops 1816 and 1818 may be optionally angled, asshown, to create a “pistol-grip” configuration. It will be appreciatedthat the finger loops 1818 and 1816 may be provided with holes largeenough to fit multiple fingers.

FIG. 20 illustrates one embodiment of an ultrasonic end effector 2006and transducer assembly 2004 positioned at the distal end of a flexiblemember 2002. In use, other components, such as a handle, may beconnected to the portion 2000.

FIGS. 21-26 show various embodiments of a surgical instrument that maybe used in endoscopic or laparoscopic environments. The surgicalinstrument may comprise a surgical device including a transducer and anend effector. The surgical instrument also may comprise a sleeveconfigured to receive the surgical device. The sleeve may include a railpositioned along its interior portion. The surgical device may comprisea feature for receiving the rail. In use, the surgical device may slidewithin the sleeve along the rail. This may allow the surgical device tobe introduced and removed from a surgical site during endoscopic orlaproscopic surgical procedures.

FIG. 21 illustrates one embodiment of an ultrasonic instrument 2101 foruse in an endoscopic or laparoscopic environment. The surgicalinstrument 2101 may be housed within a sleeve 2104. The sleeve 2104 maybe connected to an endoscope sleeve 2102 for housing the endoscope 2100.Portions of the surgical instrument 2101, e.g., a control wire, mayextend through the sleeve 2104 to a clinician, who may control thesurgical instrument 2101. The surgical instrument 2101 may be slidablewithin the sleeve 2104 into a position in view of the endoscope 2100, asshown.

The surgical instrument 2101 may comprise a transducer 2112, an endeffector 2110, and a clamp arm 2106. The clamp arm 2106 may include aclamp pad 2108. In use, the clamp pad 2108 may be brought into contactwith the end effector 2110 to provide a clamping force between tissueand the end effector 2110. For example, the surgical instrument may bemaneuvered into position relative to the tissue. The end effector 2110then may be energized and brought into contact with the tissue.According to various embodiments, the end effector 2110 may move towardthe clamp arm 2106, or the clamp arm 2106 may move toward the endeffector 2110. FIGS. 22-23 show embodiments of the surgical instrument2101 where the clamp arm 2106 comprises two support members 2114, 2116.The embodiments of FIGS. 22-23 may be utilized by drawing a loop orwedge of tissue between the two support members.

FIGS. 24-26 illustrate embodiments of a surgical instrument2401including a flexible lasso 2402. The lasso 2402 may be extendableand retractable from the surgical instrument 2401 to bring tissue intocontact with the end effector 2110. For example, a clinician may extendthe lasso 2402 to ensnare a polyp or other type of tissue. The clinicianthen may retract the lasso 2402 to pull the polyp or other tissue intocontact with the end effector 2110, which may be energized to cut and/orcoagulate the tissue. The lasso 2402 may be embodied as a cable, or as astiff ribbon material. It will be appreciated that a lasso 2402 made ofstiff ribbon material may help guide tissue to the tip of the endeffector 2110.

The instruments disclosed herein can be designed to be disposed of aftera single use, or they can be designed to be used multiple times. Ineither case, however, the instrument may be reconditioned for reuseafter at least one use. Reconditioning can include any combination ofthe steps of disassembly of the instrument, followed by cleaning orreplacement of particular elements, and subsequent reassembly. Inparticular, the instrument may be disassembled, and any number ofparticular elements or components of the instrument may be selectivelyreplaced or removed in any combination. Upon cleaning and/or replacementof particular components, the instrument may be reassembled forsubsequent use either at a reconditioning facility, or by a surgicalteam immediately prior to a surgical procedure. Those skilled in the artwill appreciate that reconditioning of a instrument may utilize avariety of techniques for disassembly, cleaning/replacement, andreassembly. Use of such techniques, and the resulting reconditionedinstrument, are all within the scope of the present application.

Preferably, the various embodiments described herein will be processedbefore surgery. First, a new or used instrument is obtained and ifnecessary cleaned. The instrument can then be sterilized. In onesterilization technique, the instrument is placed in a closed and sealedcontainer, such as a plastic or TYVEK® bag. The container and instrumentare then placed in a field of radiation that can penetrate thecontainer, such as gamma radiation, x-rays, or high-energy electrons.The radiation kills bacteria on the instrument and in the container. Thesterilized instrument can then be stored in the sterile container. Thesealed container keeps the instrument sterile until it is opened in themedical facility.

It is preferred that the instrument is sterilized. This can be done byany number of ways known to those skilled in the art including beta orgamma radiation, ethylene oxide, steam.

Although various embodiments have been described herein, manymodifications and variations to those embodiments may be implemented.For example, different types of end effectors may be employed. Also,where materials are disclosed for certain components, other materialsmay be used. The foregoing description and following claims are intendedto cover all such modification and variations.

Other than the operating examples, or where otherwise indicated, allnumbers expressing quantities of ingredients, processing conditions andthe like used in the specification and claims are to be understood asbeing modified in all instances by the term “about”. Accordingly, unlessindicated to the contrary, the numerical parameters set forth in thefollowing specification and attached claims are approximations that mayvary depending upon the desired properties sought to be obtained.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the disclosure are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical values, however, inherently contain certainerrors, such as, for example, equipment and/or operator error,necessarily resulting from the standard deviation found in theirrespective testing measurements.

Also, it should be understood that any numerical range recited herein isintended to include all sub-ranges subsumed therein. For example, arange of “1 to 10” is intended to include all sub-ranges between (andincluding) the recited minimum value of 1 and the recited maximum valueof 10, that is, having a minimum value equal to or greater than 1 and amaximum value of less than or equal to 10.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

What is claimed is:
 1. A surgical instrument, comprising: a transducerconfigured to generate an acoustic standing wave of vibratory motionalong a longitudinal axis, wherein the transducer comprises apiezoelectric stack positioned along the longitudinal axis, and whereina length of the transducer is less than ½ of the wavelength of theacoustic standing wave; and an end effector acoustically coupled to andextending distally from the transducer along the longitudinal axis;wherein a sum of the length of the transducer and a length of the endeffector is an integer multiple of ½ of the wavelength of the acousticstanding wave.
 2. The surgical instrument of claim 1, wherein thetransducer is configured to resonate at a predetermined vibrationalfrequency, and wherein the wavelength of the acoustic standing wavecorresponds to the predetermined vibrational frequency.
 3. The surgicalinstrument of claim 1, wherein the length of the transducer is greaterthan or equal to ¼ of the wavelength and less than ½ of the wavelengthof the acoustic standing wave.
 4. The surgical instrument of claim 1,wherein the end effector comprises: a waveguide acoustically coupled toand extending distally from the transducer; and a blade coupled to andextending distally from the waveguide.
 5. The surgical instrument ofclaim 4, wherein the blade is positioned at a distance equal to ¼ of thewavelength of the acoustic standing wave from a distal most node of theend effector.
 6. The surgical instrument of claim 1, wherein the endeffector comprises a proximal end and a distal end, and wherein the endeffector is configured to gain the amplitude of the acoustic standingwave between the proximal end and the distal end.
 7. The surgicalinstrument of claim 6, wherein the end effector comprises a series ofsections that alternate between sections of a first diameter andsections of a second diameter, and wherein each transition between asection of the first diameter to a section of the second diameter occursat a zero-displacement node.
 8. The surgical instrument of claim 1,wherein the sum of the length of the transducer and the length of theend effector is substantially equal to 1 wavelength of the acousticstanding wave.
 9. The surgical instrument of claim 1, wherein thetransducer is configured to generate an acoustic standing wave patternwith a predetermined amplitude at a resonant frequency.
 10. The surgicalinstrument of claim 1, wherein the transducer comprises: a transductionportion; a first resonator portion extending proximally from thetransduction portion; and a second resonator portion extending distallyfrom the transduction portion.
 11. The surgical instrument of claim 10,wherein the transducer is configured to resonate at a frequency, andwherein the length of the first resonator portion and the secondresonator portion is based on a thickness of the transduction portion, adensity and modulus of elasticity associated with the first resonatorportion and the second resonator portion, and the resonant frequency ofthe transducer.
 12. The surgical instrument of claim 1, wherein thetransducer further comprises a flange and a mass positioned along thelongitudinal axis, and wherein the piezoelectric stack is locatedbetween the flange and the mass.
 13. The surgical instrument of claim12, wherein the length of the transducer is greater than ¼ of thewavelength and less than ½ of the wavelength of the acoustic standingwave, and wherein the flange is positioned at a node of the transducer.14. A surgical instrument, comprising: a transducer configured toprovide a wave of longitudinal vibratory motion along a longitudinalaxis, wherein the transducer comprises a piezoelectric stack positionedalong the longitudinal axis, and wherein a length of the transducer isgreater than or equal to ¼ of the wavelength and less than ½ of thewavelength of the wave; and an end effector coupled to and extendingdistally from the transducer along the longitudinal axis; wherein a sumof the length of the transducer and a length of the end effector is aninteger multiple of ½ of the wavelength of the wave.
 15. The surgicalinstrument of claim 14, wherein the transducer is configured to operateat a predetermined frequency, and wherein the wavelength of the wavecorresponds to the predetermined frequency.
 16. The surgical instrumentof claim 14, wherein the end effector comprises a proximal end and adistal end, and wherein the end effector is configured to gain theamplitude of the wave between the proximal end and the distal end.
 17. Asurgical instrument, comprising: a transducer configured to generate anacoustic wave of vibratory motion along a longitudinal axis at apredetermined frequency, wherein a length of the transducer is less than½ of the wavelength of the acoustic wave; and an end effector coupled toa distal end of the transducer, wherein the end effector comprises: awaveguide coupled to and extending distally from the transducer; and ablade coupled to and extending distally from the waveguide; wherein asum of the length of the transducer, a length of the waveguide, and alength of the blade is an integer multiple of ½ of the wavelength of theacoustic wave.
 18. The surgical instrument of claim 17, wherein the endeffector comprises a proximal end and a distal end, and wherein the endeffector is configured to gain the amplitude of the acoustic wavebetween the proximal end and the distal end.
 19. The surgical instrumentof claim 18, wherein the end effector comprises a series of sectionsthat alternate between sections of a first diameter and sections of asecond diameter, and wherein each transition between a section of thefirst diameter to a section of the second diameter occurs at azero-displacement node.
 20. The surgical instrument of claim 17, whereinthe sum of the length of the transducer, the length of the waveguide,and the length of the blade is substantially equal to 1 wavelength ofthe acoustic wave.